Just curious..

My period for April was 9 days late. On the 10th day, I started cramping and had light bleeding for that day and probably half of the next day and then it was gone.. I've continued to get nauseous at random times and the headaches are so bad. I never felt my period coming and never got sore boobs like usual. If I conceived it would have been either 4/11 or 4/18. Tested 3 times, negative. But I would only be 3 or 4 weeks I think. Should I just wait it out and see if I miss my next period or test again? I thought for sure I was pregnant, but figured it would have shown up by now.. I keep reading about people getting bfps late and having periods while pregnant.. Thoughts?